CNSS gets data from the local networks and compiles it into a daily catalog.
NEIS generally ignores a good deal of local network data unless it meets certain
criteria for inclusion. The catalog of the International Data Center, which is now under
the U.N. and is difficult to obtain is even more complete listing up to 100 teleseisms
per day - NEIS tyically lists only about 10-20. ISC does not make current information
available, but is generally listing somewhere around 50-60 teleseisms per day.
The choice of which catalog to use is very important and is dependent upon
what areas and events you are interested in. For my daily reports, I generally
comb the internet sites of about 50 local, regional and teleseismic networks. The
daily catalog I come up with includes several hundred events per day only a few
of which are listed by NEIS.
Another arbitrary choice in evaluating forecasts. My general view is that all data
from as many sources as are avilable should be reviewed, if possible, before a
statement regarding the occurrence of an event is made.